This invention relates generally to electroacoustic piezoelectric transducers and, more particularly, to high frequency electroacoustic piezoelectric transducers of the type which convert electrical current to high frequency sound. Such transducers are especially useful in small loudspeakers for producing sounds of high pitch, known as tweeters.
Electroacoustic or electromechanical piezoelectric transducers are known which convert electric current to sound. Such known piezoelectric transducers, when used in small loudspeakers for producing high pitch sounds, i.e., tweeters, generally require amplification stages in order to amplify the electric current applied to the piezoelectric element or crystal so that the volume of the sound produced is sufficient to be heard. The provision of such amplification stages results in the transducer being relatively complex in construction and expensive in manufacture.
Known high frequency loudspeakers or tweeters function through a displacement of the diaphragm produced by a moving coil which receives voltage and current through a coupled inductance. Although it is known to replace the moving coil by a vibratory ceramic element, the use of a ceramic element has been limited due to the generally inferior response obtained by such devices.